Process for making mixture of cocoa or chocolate and milk and product thereof



Patented Apr. 23, 1929.

- UNITED STATES 1,710,507 PATENT OFFICE.

CHARLES E. NORTH, OF MONTCLAIR, NEW JERSEY, ASSIGNOR TO DAIRY DRINK COM-I'ANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

PROCESS FOR MAKING MIXTURE OF COCOA. OR CHOCOLATE THEREOF.

AND MILK AND PRODUCT No Drawing. Original application filed August 15,1925, Serial No. 50,485. Divided and this application filed January 29,1928. Serial No. 84,752.

thereof.

Beverages comprising a mixture of cocoa and milk or chocolate and milkhave frequently been made in the home on a small scale and usually havebeen drunk approximately when made. -Such beverages have also been madecommercially on a factory scale, but, so far as 'I am aware,difficulties have been experienced in producing such beverages becausethe cocoa or chocolate has set- 1 tled at the bottom of and the butterfat has risen to the top of the mixture if the same is kept for anyconsiderable length of time. The use of milk as the greater part of suchbeverages naturally brings the manufacture thereof within the scope ofthe business of large milk dealers, but the use of cocoa is sounfamiliar to the milk industry that the preparation of the cocoaportion of the milk is largely in the hands of those more familiar 5with cocoa and its properties.

' On a commercial scale milk and cocoa mixtures have been marketed inglass bottles. The time required for mixing, bottling, shipping anddistributin the beverages may occupy a day or more. ommercially thecocoa-milk mixtures are usually cooled and designed to be consumed in acondition which is cool rather than as the hot cocoa of home production,although such commercial mixtures may be heated if desired. The timerequired'for the manufacture of the mixtures by the milk dealer causescertain changes in the commercial product not obvious in the hothomemade cocoa-milk beverages. The mixing of the cocoa and milk orchocolate and milk, bottling and marketing of the mixtureshas beenperformed for the most part on a commercial scale by large milk dealersas a branch of their business. The cocoa has been obtained by them inthe form of a syrup which is supplied by dealers in cocoa or incocoa-syrup. Such syrup comprises cocoa, sugar and water so mixed andproportioned that it has been only necessary to add the amount specifiedon the lebels of the cans of syrup to the amount of whole fluid milkalso specified, whereupon the syrup and the milk have been mixed,pasteurized, homogenized, cooled and bottled and marketed within a fewhours or days after the bottling. Instead of using the syrup referred toas purchased on the market the milk dealer may make his own syrup, or hemay make a mixture of cocoa or chocolate and milk in deslred proportionin the usual way but on a commercial scale.

The most serious difficulties encountered by those promoting on acommercial scale the sales of cocoa and milk mixtures or chocolate andmilk mixtures for beverages is the separation of the fat of the milkwhich rises to the top of the mixtures and the separation of the cocoawhich falls by gravity to the bottom of the mixtures. The specificgravity of whole milk is 1.029. Since the specific gravity of milk fatis 0.960 and of cocoa 1470 it will be apparent that milk fat is about 8%lighter than milk and cocoa is about 44% heavier than milk. As aconsequence, if the mixturestands for only an hour or two a layer ofmilk fat can be seen on the top and a layer of cocoa on the bottom ofthe mixture in glass bottles. After standing over night there may be alayer as thick as an inch or more creamy fat on top of the mixture and alayer as thick as a half inch of dark brown cocoa or chocolate at thebottom of such mixture referred to. Such separation of the fat and cocoaor chocolate from the mixtures impairs the marketability thereof. It hasbeen proposed, as a remedy for the separation of the milk fat 85 andcocoa or chocolate in such mixtures, to pass the mixture through amachine called a homogenizer by means of which the fat globules arebroken up into such fine particles as to remain in suspension 'in themilk and fail to rise. Such machines are expensive to buy and tooperate, as they comprise a series of heavy pumps compressing the liquidunder pressures ranging from 1500 to' 6000 pounds to the square inch.Such machines have no effect on the cocoa or chocolate so far as keepingit from precipitating in the mixtures is concerned for the reason thatcocoa does not consist of fiat globules but of starchy and fibrousmaterial. As a consequence, the treatment of the mixtures byhom'ogenizers still leaves the mixtures in a condition in which thecocoa quicklysettles to the bottom forming a brown sediment.

The object of my invention is to so treat or prepare one or moreingredients of the cocoamilk or chocolate-milk mixture, either before orafter the mixture is made, as to prevent the rising of the fat globulesto the surface and the depositing of the cocoa or chocolate at thebottom of the mixture without regard to the time of retaining themixture for use.

In this specification I use the term cocoa as including commercial cocoaor chocolate,

,.foregoing by increasing the friction or viscosity of the milk li uidagainst the surfaces of the particles of at and the particles of cocoato such an extent that their respective motions upwards or downwards inthe mixture due to their differences in specific gravity from the gravitof the liquid is overcome. The friction oft e liquid against thesurfaces of the particles of fat or of solid material, such as cocoa, inthe mixture is in direct ro-' ortion to the viscosity of the liquid oruid,

y which I mean the thickness or stickiness or tenacity of the liquid orfluid. If the viscosity of water is represented by 1.0 the viscosity ofnormal fluid milk is 1.8. The thickness or viscosity of the milk fluidcan be increased in several ways. Thickeners or more viscous substancescan be added directly to the milk or to the cocoa syrup, or to themixture. Such thickeners include gelatine, agar, vegetable gums,starches, such as corn-starch, etc. Or the solids of the milk itself maybe changed so that from a liquid form they assume a more solid form andincrease the vis-' cosity of the milk. By the application of very highheat (240 F.) and pressure (15 lbs. to the sq. in.) to milk the caseinand albumen of milk may be made to assume a creamy and jelly-like form.Such heat and pressure maybe applied to the milk alone or to the milkand cocoa mixture of my beverage. In such wa s and possibly in otherways the viscosity o the milk may be increasedat will and such increasesin viscosity may be graduated and their effect on the rising of milk fatand the descent of cocoa in the mixture may be noted. The motion of fatparticles upward and of the cocoa articles downward in a mixture of milkan cocoa is fast or slow, and such motions cannot, so far as I am aware,be brought absolutely to a standstill without an increase in viscosityso great that the liquid in which these particles is suspended isabsolutely rigid, as it would be if frozen. 0n the other hand, however,the friction can be increased sufliciently to make the movement of theparticles so slow that no separations serious enough to impair thecommercial value of such mixtures will take place for days or evenweeks. I have discovered the precise points at which the viscosity andhence the friction is sufficient to prevent the rising of the fat to thetop of such mixtures for twenty-four hours. The point for fat is 2.2,which means 2.2 times as viscous as water. I have also discovered thedegree of viscosity and hence of friction necessary to prevent thesettling of cocoa to the bottom of the mixtures of cocoa and milk fortwenty-four hours. This is a viscosity of 2.5, which means a viscosity 2times as viscous as water.

One of the ways to increase the viscosity of the mixture is the use (ifthickeners in the cocoa-syrup itself before its use in making acocoa-milk mixture, such as used by the milk dealer. Cocoa syrups forthe purpose usually comprise dried cocoa powder or ground fiber,

plus sugars of various kinds, plus sufiicient.

Per cent.

Cocoa 8 Sugar 16 Thickener 2 Water 7 4 Total 100 In making of such syrupthe mixture containing the thickener may be mixed and heatcd and packedin tin cans. Among the convenient thickeners for the syrup arecornstarch, gelatine, vegetable gums, such as acacia, gum tragacanth,gum arabic, Irish moss, other gums, agar, or a mixture of lime water andsugar, known in the trade as viscogen, may be used.

Instead of the addition of a thickener to the cocoa syrup such thickenermay be added to the milk to increase the viscosity of the milk liquidbefore the syrup is mixed therewith. The proportion of thickener to beplaced in the milk can be the same as that described with respect to thesyrup. Furthermore, the cocoa and milk mixture first may be made andthen the thickener may be added thereto. It is preferable to agitate themixture containing the edible thickener sufliciently to thoroughly mixthe ingredients.

it may be done at the factory where ithe syrup When the thickener isadded tofthe syrup is made, which would make possible the sale of asyrup that would provide not only the cocoa and sweetening but also aremedy to prevent the separation of the fat and cocoa from the milk. Insuch case it would be necessary only for the milk dealer to add milk tothe thickened cocoa-syru and proceed with the manufacture of the everagein the routine way.

It may be convenient for the milk dealer to buy cocoa-syrup without athickener and add a thickener of his own at the time the mixture withmilk is made, either by adding the thickener to the syrup or by addingthe thickener to the milk before the mixture of syrup and milk is made.In such event the thickener would be weighed out in proper proportions,melted and diluted as necessary and mixed with the syrup, or with themilk, or with the syrup and milk mixture.

The use of heat without evaporation for increasing the viscosity of milkis novel, because two of the solids, not fat, are affected but in apeculiar way. The albumen in cows milk amounting to .5% of the .wholeand 4 of the solids is coagulated by heat of from 145 F. to 150 F. Casemwhich amounts to 3.5% of the whole milk and 29 of the solids iscoagulated into a jellylike mass at temperatures from 220 F. to 250 R,which may be most conveniently produced by placing the milk in closedcontainers and heating the same by steam 'under pressure. I have foundthat the application of heat to milk at temperatures of 145 F. to thatof boiling, (212 F.), in addition to the coagulation of albumen alsoaffects the fat globules by breaking up their clusters, so that insteadof clustering in small rou s the fat globules become more evenly lstriuted as scattered individuals. This exposes the entire surfaces of thefat globules to the action of friction of the milk liquid and suchfriction is increased by the coagulation of the albumen of the milk, andas a consequence of these two factors in milk heated to from 145 F. to212 F. the rising of fat imthe form of cream is greatly diminished.There is no such effect on the cocoa in cocoa and milk mixtures, becauseof the much greater difference between the specific gravity of cocoa andof milk and the fact that the increase in viscosity by the by the heatand pressure describe to increase coagulation of milk albumen alone isnot enough to prevent the falling of the cocoa fibers in the mixture.When the temperature of the milk and cocoa mixture is raised above 220F., (in practise I- use 240 F. for about thirty minutes) ,and the caseinis coagulated into a jelly-like mass the increase in viscosity of themilk becomes so great that its friction on the cocoa fibers brings themalmost to a standstill. Under such conditions motion of the cocoa fibersis so slow that they remain in suspension in the mixture for days oreven weeks.

I When heat alone is applied to the mixture or to the milk certainirregularities in the desired results may occur due to lack of care ofthe operator in controlling a) the acidity of the mixture (6) or theperiod of heating (0) or the temperature and pressure which may at timesfail to'prevent the deposit of small amounts of cocoa fiber in thebottom of the mixture. Such irregularities can be entirely overcome if athickener, such as cornstarch, is added -to the cocoa-milk mixture or tothe milk and heat is then applied as described to the mixture or to themilk. This result is attained by the assistance of the thickener byadding to the viscosit normally produced by the heat treatment. hy thelatter procedure desired results may be attained I to prevent rising ofthe milk fat or the descent of the cocoa fibers in the mixture with lessskill than is required by the use of the heat treatment alone. Thesterilizing feature of the heat treatment is a desirable adjunct in anyevent in order to prevent decomposition of the mixture.

For the purpose of subjectingothe cocoa and milk mixtures to hightemperatures and pressures the mixture may be placed in glass bottles ortins or any convenient form of container. The ordinary t pe of steamchest or sterilizer may be used orthe purpose of heating, but forcommercial purposes and to avoid excessive breakage of glass bottles Iprefer to use large kettles in which the bottles containing the mixturemay be submerged under water. The covers of the kettles may be bolteddown against gaskets and steam under pressure from a steam boiler may begradually injected into the kettles until the water is heated to 240 F.and the corresponding pressure attained, which pressure of about 15 lbs.to the square inch within the closed bottles or containers will beautogenous. After the containers have been subjected to the heat andpressures set forth for a desired period of time, say at 240 F. forabout 30 minutes, the steam may be exhausted from the kettle, by openinga suitable valve connected therewith, and after the water in the kettlehas sufliciently cooled the containers may be removed with theircontentsready for use or shipment.

If preferred the milk alone ma be treated The effect of such hi htemperature andressure as 240 F. and 15 lbs. to the square mchfor aperiod of about thirt minutes is not only to change the nature 0 thealbumen and casein and increase the viscosity of milk but also serves tokill all bacteria,

yeasts and moulds in such mixtures. In short, the high temperatures andpressures sterilize these mixtures and by sterilization entirely removetheir perishability so far as the growth of micro-organisms isconcerned. As a consequence when proper care is taken to providecontainers which are sealed so as to permit no risk of contamination thecocoamilk mixtures so made not only do not separate but also do notdecompose.

The manufacturer may, however, heat milk or skim milk containing thethickener in open vessels such as pails, or cans, or tanks, placingthese in steam pressure chests such as those employed in the canningindustry and after heating the contents to 240 F. at a pressure of 15lbs. to the square inch for between twenty-five and thirty minutes hemay then remove the milk from the pressure chest and mix cocoa orchocolate, a thickener and sugar with the same andplace the mixture inhis final containers, such as cans and bottles. By such practice hewould obtain mixtures which will not separate but would sacrifice someof the advantages of sterilization and keeping qualities for a Widerchoice of containers and of closures for the same.

If preferred the cocoa syrup containing the thickener previouslydescribed may be mixed with the milk before the latter is subjected tothe heat and pressure described,

or the thickener may be added to the milk before the cocoa-syru is addedand then such mixture may be sub ected to such heat and pressure.

The proportions of milk and cocoa syrup suitable for a beverage may bethree quarts of milk to one quart of cocoa-syrup including theproportion of thickener before referred to. The addition of a thickeneralone (such as corn-starch) to a cocoa-milk mixture will effectivelyprevent the separation and the settling of cocoa in such mixtures. Butwithout the sterilizing effect of heat such mixtures are perishable asthey will be decomposed in a few days by the action of micro-organisms.

Having now described my invention what I claim is 1. That step in theprocess of producing cocoa-milk mixtures which consists in the additionof a thickener and the application of heat the mixture to increase theviscosity of the fluid to such an extent that by its friction on theirsurfaces the cocoa fibers remain in suspension.

' 2. That step in the process of producing cocoa milk mixtures whichconsists in the addition of corn-starch and the application of heat tothe mixture to increase the viscosity of the fluid to such an extentthat by its friction on their surfaces the cocoa fibers remain insuspension.

3. That step in the process of producing cocoa-milk mixtures whichconsists in the addition of a thickener to the mixture to increase theviscosity of the fluid to such an extent that by its friction on theirsurfaces the cocoa fibers remain in suspension, and heating the mixtureto a temperature of about 240 F. at a pressure of about 15 lbs. to thesquare inch for a period of about thirty min-' 5. A fluid beveragecomprising cocoa, milk' and a thickener in which the milk is in acoagulated condition as a result of heat and pressure treatment and inwhich the combined viscosity of the coagulated milk and the thickener issufiicient by the friction on their surfaces to hold substantially allthe cocoa fibres in suspension.

CHARLES E. NORTH.

